Integration of fluorinated nano-crystal memory cells with 4.6F/sup 2/ size by landing plug polysilicon contact and direct-tungsten bitline

This paper reports the first full process integration of nano-crystal memory (NCM) with 4.6F/sup 2/ cell (size: 0.0777 /spl mu/m/sup 2/) based on NOR type, which is achieved by landing plug polysilicon contact (LPC) and direct tungsten (W) bitline (BL). Robust 4-threshold voltage (VT) states for 2 bits operation per cell are verified. Also, the comparable characteristics to NCM with conventional silicide BL contact are obtained and NCM reliability is significantly improved by properly fluorinated effect while still keeping process compatibility and controllability, which is the only alternative for volume manufacture of high density NCM.